Role of Angiogenic Growth Factor Receptors, Tie 1 and Tie 2, in Metastatic Potential of Breast Cancer

摘要

Angiogenesis determines tumor progression and microvessel density correlates with metastatic potential of breast cancer. Normal development of the vascular network in the embryo requires angiogenesis which is regulated by expression of novel endothelial cell receptors, Tie 1 and 2. Tie 2 function is regulated by two ligands, Angiopoietin 1 and its naturally-occurring antagonist, Angiopoietin 2. Expression of these receptors and their ligands has been detected in areas of active vascular remodeling and in wound healing. We generated molecular probes for analysis of expression of Tie 1, Tie 2, Angiopoietin 1 and 2 in human and rodent tissues and established cell lines which express the Tie 2 receptor. We also developed a model of human breast cancer in nude rat. We detected expression of Tie receptors in breast tissue and found differences in their expression in malignant and benign breast tumors These exciting observations suggest that Tie 2 play a role in angiogenesis associated with breast cancer.